Abstract:

Objective  To investigate the effect and mechanism of α-Melanocyte stimulating hormone（α-MSH）on fatty acid oxidation in skeletal muscle. Methods  Saline or α-MSH were subcutaneously injected  into 8-week C57BL/6J male mice , and the carnitine palmitoyl transferase-1（CPT-1） activities were measured 0, 0.5, 1, 3 and 5 hours after treatment. Melanocortin receptor(MCR) subtypes in the muscle and C2C12 cells were measured by RT-PCR, and the effect of α-MSH on palmitate oxidation was also analyzed. Results  CPT-1 activities were significantly increased 1 and 3 hours after treatment(P＜0.05）. MC1R, MC3R, MC4R and MC5R were expressed in C2C12 cells and primary cultured skeletal muscle, and α-MSH increased the palmitate oxidation in a dose-dependently way. Conclusion  α-MSH might  increased fatty acid oxidation in skeletal muscle through MCR.

Key words: α-MSH; Melanocortin receptor; Fatty acid oxidation